Nuclear winter

John
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Re: Nuclear winter

Post by John »

Higgenbotham wrote: > An EMP attack isn't high on my list of worries either. That's
> because there are easier (and probably much more reliable - with
> emphasis on the word "much") ways to create havoc.

> I'd posted a little bit about Buffett's meeting over the weekend
> in the other thread. Buffett is an insurance man. Along this
> vein, I believe he said in the meeting that he estimates a 2%
> yearly chance of a cyber attack that causes greater than $400
> billion in damage. I believe he also said that is his number one
> worry.
The reason for my interest in the emp attack is because of the claim
that it would kill 90% of the population within a year.

Buffett isn't worried about killing off the population. He just wants
to make money.

Higgenbotham
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Re: Nuclear winter

Post by Higgenbotham »

Higgenbotham wrote:We know the strength of an electromagnetic field that is stationary varies inversely with the square of the distance but I don't think that applies if it travels as a pulse or wave.
What I mean by that is assuming all of the energy remains at the blast site so many miles from the earth would underestimate the effects. That would be the worst case (the weakest estimated effect).
John wrote:So if the strength of the emp explosion is
X, then the strength of the attack per square mile is X/3.5 million.
That's the best case (for the strongest estimated effect). In other words, that assumes all of the ability to generate an EMF at the blast site gets transferred to ground level simultaneously and dispersed uniformly over that area (taking into account variations in distance).

As the energy travels to the earth, I believe some of it will be dissipated (as heat) as it travels. Also, although the EMF will have more effect at the earth's surface due to the fact that it is transferred through space (rather than remaining stationary at the blast site), it will be dispersed in the sense that it doesn't all arrive at the earth's surface simultaneously.
While the periphery breaks down rather slowly at first, the capital cities of the hegemon should collapse suddenly and violently.

Higgenbotham
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Re: Nuclear winter

Post by Higgenbotham »

The real world application I was thinking about when I posted the above is high voltage power lines. In that case, there is a stationary power line fixed in space. If someone takes a gauss meter and measures the electromagnetic field, the strength of the field will quickly drop off with distance. But if the same strength electromagnetic field were generated by a nuclear blast the strength of the field would drop off less as a function of distance from the blast site. On the other hand (and I could be wrong about this), it will drop off much faster than predicted by uniform distribution through space at constant velocity.
While the periphery breaks down rather slowly at first, the capital cities of the hegemon should collapse suddenly and violently.

Higgenbotham
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Re: Nuclear winter

Post by Higgenbotham »

In thinking about this more, I thought it would be important to consider the mechanism by which any ions are generated. Finally, I decided it was time to stop thinking and start reading. This is really complicated.
The E1 pulse is the very fast component of nuclear EMP. E1 is a very brief but intense electromagnetic field that induces very high voltages in electrical conductors. E1 causes most of its damage by causing electrical breakdown voltages to be exceeded. E1 can destroy computers and communications equipment and it changes too quickly (nanoseconds) for ordinary surge protectors to provide effective protection against it, although there are special fast-acting surge protectors (such as those using TVS diodes) that will block the E1 pulse.

The mechanism for a 400 km high-altitude burst EMP: gamma rays hit the atmosphere between 20–40 km altitude, ejecting electrons which are then deflected sideways by the Earth's magnetic field. This makes the electrons radiate EMP over a massive area. Because of the curvature and downward tilt of Earth's magnetic field over the USA, the maximum EMP occurs south of the detonation and the minimum occurs to the north.[20]
E1 is produced when gamma radiation from the nuclear detonation ionizes (strips electrons from) atoms in the upper atmosphere. This is known as the Compton effect and the resulting current is called the "Compton current". The electrons travel in a generally downward direction at relativistic speeds (more than 90 percent of the speed of light). In the absence of a magnetic field, this would produce a large, radial pulse of electric current propagating outward from the burst location confined to the source region (the region over which the gamma photons are attenuated). The Earth's magnetic field exerts a force on the electron flow at a right angle to both the field and the particles' original vector, which deflects the electrons and leads to synchrotron radiation. Because the outward traveling gamma pulse is propagating at the speed of light, the synchrotron radiation of the Compton electrons adds coherently, leading to a radiated electromagnetic signal. This interaction produces a very large, but very brief, electromagnetic pulse over the affected area.[21]
While the periphery breaks down rather slowly at first, the capital cities of the hegemon should collapse suddenly and violently.

John
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Re: Nuclear winter

Post by John »

OK, so I guess that explains it. An emp blast over North Dakota would
result in the E1 electrons being sprayed over the entire country, from
California to Maine, and fry all the electronics.

Higgenbotham
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Re: Nuclear winter

Post by Higgenbotham »

John wrote: OK, so I guess that explains it. An emp blast over North Dakota would
result in the E1 electrons being sprayed over the entire country, from
California to Maine, and fry all the electronics.
Electrons generated close to the earth's surface and hitting nearly all at once at nearly the speed of light is about as bad as it gets, as far as a mechanism goes for frying electronics. Beyond that, that mechanism is way too complicated for somebody like me to have a clue as to how to quantify it in order to know whether thresholds would likely be exceeded.
While the periphery breaks down rather slowly at first, the capital cities of the hegemon should collapse suddenly and violently.

Higgenbotham
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Joined: Wed Sep 24, 2008 11:28 pm

Re: Nuclear winter

Post by Higgenbotham »

One thing I think can be said is the limiting factor is that there are only so many electrons that can be stripped out of the atmosphere. Probably most of those would come off the oxygen molecules, as nitrogen is more inert than oxygen.
While the periphery breaks down rather slowly at first, the capital cities of the hegemon should collapse suddenly and violently.

Higgenbotham
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Joined: Wed Sep 24, 2008 11:28 pm

Re: Nuclear winter

Post by Higgenbotham »

According to this, gamma rays will strip electrons off both oxygen and nitrogen.
All the bursts astronomers have recorded so far have come from distant galaxies and been harmless on the ground, but if one occurred within our galaxy and was aimed straight at us, the effects could be devastating, according to astrophysicist Adrian Melott of the University of Kansas in Lawrence.

The Earth’s atmosphere would soak up most of the gamma rays, Melott says, but their energy would rip apart nitrogen and oxygen molecules, creating a witch’s brew of nitrogen oxides, especially the toxic brown gas nitrogen dioxide that colours photochemical smog (see graphic).
https://www.newscientist.com/article/dn ... -on-earth/
While the periphery breaks down rather slowly at first, the capital cities of the hegemon should collapse suddenly and violently.

Higgenbotham
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Joined: Wed Sep 24, 2008 11:28 pm

Re: Nuclear winter

Post by Higgenbotham »

Will gamma rays ionize inert gas?

Frank Duncan
Frank Duncan, Chemist, retired, Radiation Safety Officer, retired, Class III Licensed Radiographer in Louisiana, retired
Yes. Gamma rays will ionize ANY gas. The gas used in a Geiger Counter tube is usually helium, argon, or neon - all inert gases. . They will also ionize liquids and solids. The ionization in solids can be used to determine the rate of exposure to radiation.

Stephen Frantz
Stephen Frantz, Former Director of the Reed College Nuclear Reactor
Yes. Normally the gas used in gas-filled detectors is an inert gas.
Gamma rays will ionize any gas.
https://www.quora.com/Will-gamma-rays-ionize-inert-gas
While the periphery breaks down rather slowly at first, the capital cities of the hegemon should collapse suddenly and violently.

Higgenbotham
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Joined: Wed Sep 24, 2008 11:28 pm

Re: Nuclear winter

Post by Higgenbotham »

Automobiles were subjected to EMP environments under both engine turned off and
engine turned on conditions. No effects were subsequently observed in those automobiles
that were not turned on during EMP exposure. The most serious effect observed on running
automobiles was that the motors in three cars stopped at field strengths of approximately
30 kV/m or above. In an actual EMP exposure, these vehicles would glide to a
stop and require the driver to restart them. Electronics in the dashboard of one automobile
were damaged and required repair. Other effects were relatively minor. Twenty-five
automobiles exhibited malfunctions that could be considered only a nuisance (e.g.,
blinking dashboard lights) and did not require driver intervention to correct. Eight of the
37 cars tested did not exhibit any anomalous response.
http://www.empcommission.org/docs/A2473 ... on-7MB.pdf
John wrote: Trevor, the following is an exchange I had on Breitbart:

TheLastPlainsman wrote: > My thoughts on it were that once the Chinese felt that
> they were losing any future conventional conflict, they will
> detonate a 20 MT about 25 miles above the continent and it would
> wipe out every power grid and every electronic device. That would
> include every gasoline powered car made since 1982, some diesels
> vehicles from 93 onward, every jet, train, semi, cell phone, and
> watch."
While the periphery breaks down rather slowly at first, the capital cities of the hegemon should collapse suddenly and violently.

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